A celebration of everything from 'kawaii' culture to sushi and ramen, the one-day Moshi Moshi Nippon Festival is part of an initiative to promote Japanese pop culture internationally and, more importantly, your chance to experience contemporary Japan from a dizzying variety of angles. Taking the stage at the Tokyo Metropolitan Gymnasium in Sendagaya are stars like pop princess Kyary Pamyu Pamyu and 'otaku idol' group Dempagumi.inc, while fashion shows and the like will also take place. A wide assortment of promotional booths will be set up, allowing you to participate in a variety of fun workshops. Furthermore, the area around the venue will feature DJ performances, a temporary food court serving festival grub like yakisoba and takoyaki, and opportunities for trying traditional matsuri activities like cork gun shooting and wanage (quoits).
Interestingly, all non-Japanese citizens can get in for free: register* on the festival's official website, bring your ticket along with a passport or residence card, and display these at the gate. Hey, they'll even give you a free food ticket on top of it all.
*Note: registration at the door is also possible.